1. Field of the Invention
The present invention relates to an improved process for preparing organometallic polymers each having a main chain constituted of silicon and/or germanium or having a main chain constituted of a linkage of silicon or germanium in combination with carbon and further having a side chain constituted of an organic hydrocarbon residue. More particularly, it relates to novel processes for preparing such polyorganosilane compounds (also referred to as "organosilane polymers") and a polyorganogermane compounds (also referred to as "organogermane polymers").
2. Prior Art Statement
Linear polymers having silicon-silicon bonds ((R.sub.1 R.sub.2 Si).sub.n) attract increasing attention as they are applied for use as novel SiC precursors, new type photo-resists, photo-initiators and photosensitive materials for electrophotography. Details of the characteristics and functions of such polymers are disclosed, for example, by R. West, J. Organomet Chem., 300, 327 to 346 (1986), M. STOLKA et al., J. Polym. Sci., Part A, Polym. Chem. 25, 823 to 827 (1987) and M. STOLKA et al , U.S. Pat. No. 4,618,551, these prior publications being incorporated herein by reference.
As a process for synthesizing an organosilane or organogermane polymer having a main chain constituted of silicon or germanium or a main chain constituted of either one or both of silicon and germanium in combination with carbon, it has been known in the art a process wherein the objective polymer is produced by subjecting a dihalide of corresponding organic hydrocarbon to dehalogenating condensation by the use of an alkali metal, the reaction being represented by the following reaction formula of: ##STR1## wherein M is silicon or germanium, or a hydrocarbon residue having silicon or germanium; X is a halogen atom; and Y and Z each stands for an organic hydrocarbon residue. When a mixture of plural monomers is used in the reaction represented by the preceding reaction formula, a copolymer may be produced. Details of such reaction may be had by referring to P. Trefanas et al., Journal of Polymer Science, Polymer Chemistry Edition, Vol. 23, pp 2099 to 2107 (1985), "Organogermane Homopolymers and Copolymers with Organosilanes", which will be incorporated herein as reference liternature.
However, the yield of a high polymer attainable by this known process is generally low, and particularly the yield of a high polymer which has a molecular weight of more than 100,000 and properties to be readily molded in a form of film or like materials is so low as less than 10%.